Printers : Types of Printers | Working & Differences between Daisy Wheel, Dot Matrix , Inkjet & Laser Printers - EngineersGarage Ashok Sharma What is a Printer? A printer is an electromechanical device which converts the text and graphical documents from electronic form to the physical form. Generally they are the external peripheral devices which are connected with the computers or laptops through a cable or wirelessly to receive input data and print them on the papers. A wide range of printers are available with a variety of features ranging from printing black and white text documents to high quality colored graphic images. Quality of printers is identified by its features like color quality, speed of printing, resolution etc. Modern printers come with multipurpose functions i.e. they are combination of printer, scanner, photocopier, fax, etc. To serve different needs there are variety of printers available that works on different types of technologies. Types of Printers Since the invention of the printing technology, a variety of technologies have been employed in computer printers. Broadly printers are categorized as impact and non impact printers. Impact printers are the type of printers in which a key strikes the paper to make a letter. The examples of Impact printers are Daisy wheel and Dot matrix printers.

While non-impact printers do not operate by striking a head against a ribbon. Inkjet printers and laser printers are the non-impact printers. The most popular printers are described. 1. Daisy Wheel Printers Daisy wheel printers print only characters and symbols and cannot print graphics. They are generally slow with a printing speed of about 10 to 75 characters per second. By 1980 daisy wheel printers were the dominant printers for quality printing but since the prices of laser and inkjet printers have declined and quality of dot matrix printers has been improved, the daisy wheel printers are now obsolete. Working of daisy wheel printers is very similar to typewriters. A circular printing element (known as daisy wheel, shown in the below image) is the heart of these printers that contains all text, numeric characters and symbols mould on each petal on the circumference of the circle. The printing element rotates rapidly with the help of a servo motor and pauses to allow the printing hammer to strike the character against the paper. What is Printer (Types of Printers Explained)? Webopedia Definition output device A printer is any device that prints text or illustrations on paper. There are many different types of printers.

In terms of the technology utilized, printers fall into the following categories: daisy-wheel : Similar to a ball-head typewriter, this type of printer has a plastic or metal wheel on which the shape of each character stands out in relief. A hammer presses the wheel against a ribbon, which in turn makes an ink stain in the shape of the character on the paper.Daisy-wheel printers produce letter-quality print but cannot print graphics . dot-matrix : Creates characters by striking pins against an ink ribbon. Each pin makes a dot , and combinations of dots form characters and illustrations. ink-jet : Sprays ink at a sheet of paper. Ink-jet printers produce high-quality text and graphics. laser : Uses the same technology as copy machines. Laser printers produce very high quality text and graphics. LCD & LED :Similar to a laser printer, but uses liquid crystals or light-emitting diodes rather than a laser to produce an image on the drum. line printer : Contains a chain of characters or pins that print an entire line at one time. Line printers are very fast, but produce low-quality print. thermal printer : An inexpensive printer that works by pushing heated pins against heat-sensitive paper. Thermal printers are widely used in calculators and fax machines .

Printer Characteristics Printers are also classified by the following characteristics: quality of type: The output produced by printers is said to be either letter quality (as good as a typewriter), near letter quality , or draft quality . Only daisy-wheel, ink-jet, and laser printers produce letter-quality type. Some dot-matrix printers claim letter-quality print, but if you look closely, you can see the difference. speed: Measured in characters per second (cps) or pages per minute (ppm), the speed of printers varies widely. Daisy-wheel printers tend to be the slowest, printing about 30 cps. Line printers are fastest (up to 3,000 lines per minute). Dot-matrix printers can print up to 500 cps, and laser printers range from about 4 to 20 text pages per minute. impact or non-impact: Impact printers include all printers that work by striking an ink ribbon. Daisy-wheel, dot-matrix, and line printers are impact printers. Non-impact printers include laser printers and ink-jet printers. The important difference between impact and non-impact printers is that impact printers are much noisier.

graphics:Some printers (daisy-wheel and line printers) can print only text. Other printers can print both text and graphics. fonts : Some printers, notably dot-matrix printers, are limited to one or a few fonts. In contrast, laser and ink-jet printers are capable of printing an almost unlimited variety of fonts. Daisy-wheel printers can also print different fonts, but you need to change the daisy wheel, making it difficult to mix fonts in the same document . Impact Printers Next 7.2. Impact Printers Impact printers are the oldest printing technologies still in active production. Some of the largest printer vendors continue to manufacture, market, and support impact printers, parts, and supplies. Impact printers are most functional in specialized environments where low-cost printing is essential. The three most common forms of impact printers are dot-matrix, daisy-wheel, and line printers. 7.2.1. Dot-Matrix Printers The technology behind dot-matrix printing is quite simple. The paper is pressed against a drum (a rubber-coated cylinder) and is intermittently pulled forward as printing progresses. The electromagnetically-driven printhead moves across the paper and strikes the printer ribbon situated between the paper and printhead pin.

The impact of the printhead against the printer ribbon imprints ink dots on the paper which form human-readable characters. Dot-matrix printers vary in print resolution and overall quality with either 9 or 24-pin printheads. The more pins per inch, the higher the print resolution. Most dot-matrix printers have a maximum resolution of around 240 dpi (dots per inch). While this resolution is not as high as those possible in laser or inkjet printers, there is one distinct advantage to dot-matrix (or any form of impact) printing. Because the printhead must strike the surface of the paper with enough force to transfer ink from a ribbon onto the page, it is ideal for environments that must produce carbon copies through the use of special multi-part documents. These documents have carbon (or other pressure-sensitive material) on the underside and create a mark on the sheet underneath when pressure is applied. Retailers and small businesses often use carbon copies as receipts or bills of sale. 7.2.2. Daisy-Wheel Printers If you have ever worked with a manual typewriter before, then you understand the technological concept behind daisy-wheel printers. These printers have printheads composed of metallic or plastic wheels cut into petals.

Each petal has the form of a letter (in capital and lower-case), number, or punctuation mark on it. When the petal is struck against the printer ribbon, the resulting shape forces ink onto the paper. Daisy-wheel printers are loud and slow. They cannot print graphics, and cannot change fonts unless the print wheel is physically replaced. With the advent of laser printers, daisy-wheel printers are generally not used in modern computing environments. 7.2.3. Line Printers Another type of impact printer somewhat similar to the daisy-wheel is the line printer. However, instead of a print wheel, line printers have a mechanism that allows multiple characters to be simultaneously printed on the same line. The mechanism may use a large spinning print drum or a looped print chain. As the drum or chain is rotated over the paper's surface, electromechanical hammers behind the paper push the paper (along with a ribbon) onto the surface of the drum or chain, marking the paper with the shape of the character on the drum or chain. Because of the nature of the print mechanism, line printers are much faster than dot-matrix or daisy-wheel printers.

However, they tend to be quite loud, have limited multi-font capability, and often produce lower print quality than more recent printing technologies. Because line printers are used for their speed, they use special tractor-fed paper with pre-punched holes along each side. This arrangement makes continuous unattended high-speed printing possible, with stops only required when a box of paper runs out. 7.2.4. Impact Printer Consumables Of all the printer types, impact printers have relatively low consumable costs. Ink ribbons and paper are the primary recurring costs for impact printers. Some Impact printers (usually line and dot-matrix printers) require tractor-fed paper, which can increase the costs of operation somewhat. PERIPHERALS - Beyond the Daisywheel - New Laser Printers - NYTimes.com PERIPHERALS; Beyond the Daisywheel: New Laser Printers By L. R. SHANNON Published: December 26, 1989 THE standard in business correspondence used to be the electric typewriter, with its crisp, clear letters. So when the personal computer began to replace the typewriter, the printer of choice was the daisywheel, which is basically an adapted typewriter head.

The daisywheel, named for its flower-like arrangement of letters, numbers and other characters around a circular gadget,a daisy, produced pages that were every bit as sharp as the typewriter's. The trouble with the daisywheel was its lack of speed and versatility. Although it could turn out words faster than a human typist could (a speed of 35 characters a second was not uncommon), it was still slow compared with what the computer was capable of churning out. And it could produce only the characters that were actually on its wheel; forget about graphics or different type faces. The next step was the dot-matrix printer, which built characters out of a matrix of tiny wires (9 or, more recently, 18 or 24) that put ink dots on the paper. It was much faster than a daisywheel. The problem was that the dots were too often visible and the characters sometimes crude. The dot-matrix printer gave the computer printout a bad name. Better dot-matrix printers could be used in what was usually called near- letter-quality mode, that is, almost as good as a daisywheel. The trade-off was lost speed, which also meant a longer time for listening to the irritating whine.

For most of us, however, the printer's ability to produce graphics, a variety of type faces and anything else the software programmer had thought of was worth the trade-off. Only the fussiest manager, correspondent or editor could object to its quality, at its best. Then there were ink-jet printers, which squirted the dots on the page, and laser printers, essentially an adaptation of photocopying technology. Laser printers were fast, versatile and capable of producing pages so good they almost looked as if they had been professionally typeset. The trouble was that they were also big, heavy and very expensive. It was hard for an individual or small office to justify the cost. Now, Hewlett Packard has made a laser printer that is hard to resist. Its new Laserjet IIP is 14 inches wide, 16 inches deep and 8.25 inches high, weighs 22 pounds and carries a list price of $1,495. But it is available for less; I found one shop that was selling it for $965. Setting up the IIP is a snap.

The ''Getting Started Guide,'' with line drawings, details the steps so clearly (''Remove the printer from its box'') that a novice should be able to follow them. The only possible hitch is editing, or creating, an Autoexec.Bat file, the collection of commands that the DOS operating system looks for when you turn your computer on. But with care, the task can be accomplished, even when, as in my case, there was a mysterious conflict between commands in my current file and a command the IIP requires. The printer has both serial and parallel ports, so it can be attached to a computer with either kind of plug. It prints up to four pages a minute, slow by laser-printer standards, and holds 50 sheets of paper in its tray, not enough for a busy office, but adequate for home or home-office use. (A 250-page tray is an optional extra.) The built-in typeface is Courier, which comes in six combinations of spacing, size and weight , plus one versionof a face called Line Printer. Additional fonts may be purchased from Hewlett Packard and other suppliers, either in the form of cartridges that plug into the printer or on disk.

A laser printer is a special-purpose computer with a mind of its own. Because it produces whole pages at a time, rather than one character after another, that mind must have sufficient memory. The 512 kilobytes that come with the IIP are enough for ordinary text, but once you start mixing fonts or adding graphics, memory gets used up fast. An uncomplicated page made with Timeworks' Publish-It program was too much for the printer. The IIP can hold up to four megabytes of additional memory, but plan on spending $200 to $350 a megabyte. In addition to the ''Getting Started Guide,'' the package contains a detailed manual, a ''Software Applications Notes'' book showing how the printer works with seven popular programs and a little catalogue of supplies and accessories. The toner cartridge, included in the purchase price, should be good for about 3,500 pages, the company says. Replacement cartridges sell for about $70. Now your letters, too, can look as if you sent them out to a job shop for printing. What is daisy-wheel printer? Webopedia Definition contone printer A type of printer that produces letter-quality type.

A daisy-wheel printer works on the same principle as a ball-head typewriter. The daisy wheel is a disk made of plastic or metal on which characters stand out in relief along the outer edge. To print a character, the printer rotates the disk until the desired letter is facing the paper. Then a hammer strikes the disk, forcing the character to hit an ink ribbon, leaving an impression of the character on the paper. You can change the daisy wheel to print different fonts . Daisy-wheel printers cannot print graphics , and in general they are noisy and slow, printing from 10 to about 75 characters per second . As the price of laser and ink-jet printers has declined, and the quality of dot-matrix printers has improved, daisy-wheel printers have become obsolete. Daisywheel Question: 192-character Printwheel Types - Google Groups Daisywheel Question: 192-character Printwheel Types Showing 1-36 of 36 messages It took quite a bit of searching, but I was eventually able to find, in an old InfoWorld or Computerworld displayed by Google Books, a picture of a daisywheel for a Diablo ECS printer.

It showed that the letters were aligned on the printwheel in the same direction, so that the daisywheel would have to move up and down to switch between the inner and outer rings. I worked with a Ricoh printer that had a smaller 128-character printwheel that worked in the same way. And the thimbles of the NEC spinwriter also had 128 characters, but because the movement was now along the thimble's axis of rotation, the thimble could be moved up and down without moving the motor that turned it. I did find out that the Wide Track printer was made by Qume - that was the one that had two printhead assemblies, so that you had extra flexibility by using two (96-character) daisywheels at once. But I can't remember the maker - it was a major maker of daisywheel printers, and I thought it was different from Qume - of an ingenious kind of 192-character daisywheel. In that daisywheel, the characters on the outer row were placed at an angle.

So the printwheel and the motor that turned it simply moved in the same horizontal direction as used for advancing along the paper in printing in order to present the characters in the outer row to the hammer. Does anyone remember who made this ingenious type of extended- character printwheel? On Dec 6, 2:29 pm, Quadibloc < jsav...@ecn.ab.ca > wrote: > Does anyone remember who made this ingenious type of extended- > character printwheel? One can buy new typewriters using a daisywheel for about $100 (made by Brother). However, apparently these are free standing alone and not connectable to anything. I was wondering if they make an _inexpesive_ daisy wheel typewriter that has a USB or parallel port in it to use as a computer printer. Or, do they still make daisy wheel output printers? (A friend gave me his old daisywheel printer that works great, but the inkers are all dry and they don't make replacements anymore.) So long as it is a fabric ribbon, and not film, you should be able to re-ink it.

On Dec 6, 1:03 pm, hanco...@bbs.cpcn.com wrote: > One can buy new typewriters using a daisywheel for about $100 (made by > Brother). Now, that's interesting. I had thought that the typewriter was dead - except for some exotic devices made by Brother that used heat to transfer ink from a film ribbon to the paper. I wish that someone would make a _fancy_ daisywheel typewriter. One print hammer. Two daisywheels - with up to _four_ concentric circles of characters each, using the idea of slanting the characters, so that the wheels only move horizontally. Proportional spacing? Yes, indeed. But in addition, the option of changing the basic unit from 1/60", as used in normal typing, to other values... such as 1/72", 1/84", and 1/96". Denoted by little red, yellow, and blue triangles on the daisywheels, perhaps, if the license could be purchased from IBM... But also intermediate values would be available!

So when using different unit sizes, one could only set tabs and margins at 1/6" locations... the color coding might be 1/54" - purple And vertical spacing would be in increments of 1/72", of course. Thus, 11-point Press Roman might have a red triangle on it, and 9-point Press Roman a yellow triangle... but now, instead of also having a yellow triangle, and being too narrow, 10-point Press Roman could have an *orange* triangle, and thus be just right. (Furthermore, with today's microchips, the italics wouldn't have to use exactly the same spacing as the regular characters... yay Monotype, boo Linotype). Who says you need a laser printer to type away in four-line mathematics? > One can buy new typewriters using a daisywheel for about $100 > (made by Brother). However, apparently these are free > standing alone and not connectable to anything. > I was wondering if they make an _inexpesive_ daisy wheel > typewriter that has a USB or parallel port in it to use > as a computer printer.

Or, do they still make daisy > wheel output printers? It's not exactly what you're asking for...but how many afc participants recall the "Magic Fingers" device from the late 1960s, which was a matrix of solenoids that you could place over the keyboard of a Selectric typewriter to produce output from laboratory instrumentation? There were two models; on one the solenoids could hit only the top row of keys, tab, and return; another had what amounted to a full keyboard. I used the el-cheapo model in a nuclear physics lab but I only recall seeing the full-keyboard model in an advertisement. I wonder if any of those units could fit the new daisy-wheel typewriters you're referring to...or if some enterprising type could come up with an equivalent box that would fit.

Joe Morris On 2010-12-07, Joe Morris < j.c.m...@verizon.net > wrote: > > It's not exactly what you're asking for...but how many afc participants > recall the "Magic Fingers" device from the late 1960s, which was a matrix of > solenoids that you could place over the keyboard of a Selectric typewriter > to produce output from laboratory instrumentation? Don't know about Magic Fingers, but I do recall adds for RoboTyper in the '80s. On Dec 6, 5:35 pm, Quadibloc < jsav...@ecn.ab.ca > wrote: > Who says you need a laser printer to type away in four-line > mathematics? Of course, now that laser printers are ubiquitous, the cost of new fonts on daisywheels alone would make this wildly impractical and uninteresting. It's too bad something like this wasn't tried back in the days when daisywheels _mattered_. John Savard Actually, it was!

UNIX had nroff, which (along with preprocessors, eqn for math), which could do surprisingly good math on a daisywheel printer. Of course, troff, which worked from the same input files, but used a photo typesetter, could do a much nicer job. But nroff was available (and used quite a lot, at least at UC Berkeley) from around the mid 70's. I have a vague recollection that Apple had a daisywheel printer for the Lisa that could do remarkable things with a single daisywheel with a special set of glyphs. He calls himself "the Garden State's leading violist da gamba," ... comparable to being ruler of an exceptionally small duchy. --Newark (NJ) Star Ledger ( ) On Dec 6, 6:45 pm, sc...@slp53.sl.home (Scott Lurndal) wrote: > >(A friend gave me his old daisywheel printer that works great, but the > >inkers are all dry and they don't make replacements anymore.) > > So long as it is a fabric ribbon, and not film, you should be able to > re-ink it.

It's not a ribbon, but a tiny roller of some sort. I heard using that all-purpose lubricant spray (forgot the name) will freshen it up. On Dec 6, 7:35 pm, Quadibloc < jsav...@ecn.ab.ca > wrote: > Now, that's interesting. I had thought that the typewriter was dead - > except for some exotic devices made by Brother that used heat to > transfer ink from a film ribbon to the paper. I think Olivetti still makes a _manual_ portable. I think it costs more than one of the Brother units above, interestingly enough. A few years ago they had a manual standard in their catalog that was a nice machine. I was tempted to get it but I really have almost no use for it and have no space to put it. BTW, in the early 1970s, manual typewriters were very well made and balanced and relatively easy to use. Many offices and banks had them as a secondary utility typewriter. As to modern consumer-grade ink-jet printers, it bugs me that: 1) The ink is expensive; 2) There is almost no warning that the ink is running out--it just stops.

You need to keep a second one on hand just in case. 3) Printers become 'obsolete' long before they they are mechanically worn out. That is, it becomes hard and expensive to find ink for them. Further, old printers required a parallel port and AFAIK new PCs don't have them and require USB ports. I've been using a Panasonic dot-matrix for 20 years, but I think it gave up on me. >[ ... ] Further, old printers required a parallel port and AFAIK new >PCs don't have them and require USB ports. That, at least, is a solved problem: there are USB-to-parallel port adapters that are rather inexpensive and which thus can give any USB-equipped computer a parallel port; just do a search for "USB parallel adapter" on your favourite search engine and you should be able to find a bunch, starting from $6. Best wishes, > On Dec 6, 7:35=A0pm, Quadibloc < jsav...@ecn.ab.ca > wrote: > > Now, that's interesting.

I had thought that the typewriter was dead - > > except for some exotic devices made by Brother that used heat to > > transfer ink from a film ribbon to the paper. > > I think Olivetti still makes a _manual_ portable. They seem to be available through Amazon... useful for people working in the field where power is unavailable or unreliable. > [snip] > As to modern consumer-grade ink-jet printers, it bugs me that: > > 1) The ink is expensive; Well, yes, that's how you pay for the printer. You don't think that they're making money selling them for $10, do you? > 2) There is almost no warning that the ink is running out--it just > stops. You need to keep a second one on hand just in case. My experience is the reverse, they'll start saying they need new toner about two weeks after a new bottle is put in, even if it's still 3/4 full. Part of paying for the printer. > 3) Printers become 'obsolete' long before they they are mechanically > worn out. That is, it becomes hard and expensive to find ink for > them.

Further, old printers required a parallel port and AFAIK new > PCs don't have them and require USB ports. There are USB-parallel converters you could buy if you feel strongly about using the printer. > I've been using a Panasonic dot-matrix for 20 years, but I think it > gave up on me. If you don't need color, consider a small laser printer. -- Patrick >> I've been using a Panasonic dot-matrix for 20 years, but I think it >> gave up on me. > If you don't need color, consider a small laser printer. Seconded. I bought an old LaserJet 1320 several years ago. Between that and the memory upgrade and one new toner cart I bought for it, I think I spent in the neighborhood of $200, and it can sit for weeks without the print media drying up and clogging. Much less hassle and cheaper to boot. -- Joe E-mail addresses in headers are valid.

| "...the FDA takes a dim view of exploding pharmaceuticals..." -- Derek Lowe > As to modern consumer-grade ink-jet printers, it bugs me that: > > 1) The ink is expensive; > > 2) There is almost no warning that the ink is running out--it just > stops. You need to keep a second one on hand just in case. > > 3) Printers become 'obsolete' long before they they are mechanically > worn out. That is, it becomes hard and expensive to find ink for > them. Further, old printers required a parallel port and AFAIK new > PCs don't have them and require USB ports. I got fed up with all that and, for b&w work, bought an old HP Laserjet with a half-full toner (which will last me for *ages*) and a network card for the equivalent of about $50. I'd never go back to ink-jet for text-type stuff. Does nice black and white photos too, I've got a few framed up and hanging on the walls. Stan Barr plan.b .at. dsl .dot. pipex .dot. com The future was never like this!

On Wed, 8 Dec 2010 18:13:37 +0000 (UTC) Joe Thompson < sp...@orion-com.com > wrote: > >> I've been using a Panasonic dot-matrix for 20 years, but I think it > >> gave up on me. > > If you don't need color, consider a small laser printer. > > Seconded. I bought an old LaserJet 1320 several years ago. Between Thirded, I picked up an old Laserjet 2300DTN some while back. It's still on the part used toner I bought it with (apparently about 900 pages to go). I picked up another toner for it recently just so it would be handy when I eventually run this one out. > that and the memory upgrade and one new toner cart I bought for it, I > think I spent in the neighborhood of $200, IIRC it's been about €250 altogether, but it's duplex, networked and has the extra 500 sheet tray. > and it can sit for weeks > without the print media drying up and clogging.

Much less hassle and > cheaper to boot. -- Joe Indeed. I have my eye on a couple of big A3 duplex colour laser printers. If I get one of them I'll probably never have to replace the toners in it. Steve O'Hara-Smith | Directable Mirror Arrays C:>WIN | A better way to focus the sun The computer obeys and wins. | licences available see You lose and Bill collects. | I bought a Brother networked laser a couple of years ago for $75. It's a wonderful machine. I think I've replaced the toner once, and it has the intelligence to tell me the toner is getting low. I keep an inkjet win-boatanchor for color work, but I've found the Kodak photo-kiosks do a better job with photos, and are probably cheaper, too. I can see that they would work nicely for printer applications where the data transfer is all one-way (except for a "not-ready" signal), but I wouldn't think they would be able to support the bi-directional data transfer modes of the late-generation parallel ports (to support such critters as parallel-port SCSI emulation ZIP disk drives and in-circuit emulator probes for embedded microcontrollers).

For my embedded power-PC work I use a now-orphaned tool chain using just such a wiggler, and as the old PCs on my bench where this lives wear out, I have to scrounge for replacement PCs or motherboards with a "legacy port set". If anyone has actual experience in resolving this problem (such as with a PC-resident source level PPC debugger that can read the ELF files produced by my old linker and work with a contemporary USB-driven BDM debugging probe) please contact me offline. I spent a couple of weeks trying to do this with the current Freescale tool chain without success. <This message has been deleted.> unk...@googlegroups.com 12/10/10 7:03 AM On Dec 8, 4:48 pm, "John Varela" < newla...@verizon.net > wrote: > > > So long as it is a fabric ribbon, and not film, you should be able to > > > re-ink it. > > It's not a ribbon, but a tiny roller of some sort. I heard using that > > all-purpose lubricant spray (forgot the name) will freshen it up.

> Yes, that's it. Haven't tried it. Anyone know if it works? Many years ago I used a Burroughs keypunch. In one sense it was nicer than the IBM 029 because it had buffering like a 129. Anyway, it used a roller to ink the typebar to print atop the card. The printing was rather uneven, though adequate for a punch card top. While the dot-matrix image of the 029 was quite coarse, it was even. unk...@googlegroups.com On Fri, 10 Dec 2010 07:03:52 -0800 (PST), hanc...@bbs.cpcn.com wrote: >On Dec 8, 4:48 pm, "John Varela" < newla...@verizon.net > wrote: > >> > > So long as it is a fabric ribbon, and not film, you should be able to >> > > re-ink it. >> > It's not a ribbon, but a tiny roller of some sort. I heard using that >> > all-purpose lubricant spray (forgot the name) will freshen it up.

>> >Yes, that's it. Haven't tried it. Anyone know if it works? It will get rid of some rust, and displace water, but it isn't a long lasting lubricant. On 12/10/2010 10:03 AM, hanc...@bbs.cpcn.com wrote: > On Dec 8, 4:48 pm, "John Varela"< newla...@verizon.net > wrote: > >>>> So long as it is a fabric ribbon, and not film, you should be able to >>>> re-ink it. >>> It's not a ribbon, but a tiny roller of some sort. I heard using that >>> all-purpose lubricant spray (forgot the name) will freshen it up. >> > Yes, that's it. Haven't tried it. Anyone know if it works? > > Many years ago I used a Burroughs keypunch. In one sense it was nicer > than the IBM 029 because it had buffering like a 129. Anyway, it > used a roller to ink the typebar to print atop the card.

The printing > was rather uneven, though adequate for a punch card top. While the > dot-matrix image of the 029 was quite coarse, it was even. Maybe Burroughs was trying to make the keypunch printing look like their line printers. >But don't HP printers have one serious deficiency? >Or are all printers able to do this nowadays? Oh, only for the last decade or so. R's, On Dec 10, 3:56 pm, Peter Flass <Peter_Fl...@Yahoo.com> wrote: > Maybe Burroughs was trying to make the keypunch printing look like their > line printers. My college had a Burroughs and I have many documents printed by their mainframe. The print quality is attrocious. It's really bad on my report cards since they were in a carbon envelope. IBM introduced the 402 and 407 in the late 1940s, which had excellent printing quality, but were low speed. I don't know how they compared to other tabulating or accounting machines. The few old documents I've seen printed by other machines, like NCR Bookkeeping machines, isn't very impressive.

Then IBM introduced the standard-bearer of printers, the 1403, in 1959, and continued with it for S/360. Yet the other companies like Burroughs and Univac never could seem to come up with anything near as good. Their printing danced around more than a drunk at a bar. Even Univac's low speed printer sucked. On Dec 11, 8:19 pm, hanco...@bbs.cpcn.com wrote: > Yet the other companies like Burroughs and Univac never could seem to > come up with anything near as good. Their printing danced around more > than a drunk at a bar. Even Univac's low speed printer sucked. Many computer companies made their own magnetic tape drives. Sometimes this had odd results. Univac had early magnetic tape drives that used reels of metal foil instead of Mylar tape with oxide. Honeywell's Datamatic 1000 used enormous tape reels, and those used with the KDF9 were somewhat large as well. But then there was the random-access DECtape, which was an early inexpensive substitute for a conventional disk drive... the predecessor of the floppy disk.

A few of IBM's manuals were typeset conventionally, like System/360 Principles of Operation. Many were reproduced from printout on a TN print train. As a student, I used a Honeywell 516 that had a drum printer which was in excellent adjustment, so I know that print quality can be good on non-IBM equipment. But I also have a copy of a manual for a Univac operating system (prepared locally by a college with a Univac computer) the masters for which were printed in all-uppercase by a poorly-adjusted drum printer, so I know how bad it can get. Univac, of course, was a tab equipment competitor of IBM. So they were in a position to make some of their own peripherals. A lot of smaller computer companies just got their peripherals from companies that were in the peripherals business, like Potter Equipment Corporation. I think that Control Data and SDS, for example, used many of their peripherals. SDS and Digital, for example, didn't try doing their manuals on a line printer. Instead, they weren't ashamed to advertise the competition a little by using an IBM Executive typewriter with the Mid-Century typestyle.

(Looks a little like Futura.) Others used Documentary or Modern. Univac would not stoop to that, and as we've seen, their line printers didn't cut it. So, when they didn't go all-out for typesetting... many of their manuals were done on a Vari-Typer. The one derived from the old Hammond typewriter. >A few of IBM's manuals were typeset conventionally, like System/360 >Principles of Operation. Many were reproduced from printout on a TN >print train. Make that "the early S/360 PoO" were typeset. The later ones were mastered on a 1403 with a TN train, or at least had that style (monospaced, typewriter-style font, and rather cheap-looking). [...] > But I also have a copy of a manual for a Univac >operating system (prepared locally by a college with a Univac >computer) the masters for which were printed in all-uppercase by a >poorly-adjusted drum printer, so I know how bad it can get.

In the late 1960s Univac was one of the bidders for the replcement mainframe at my PPOE. The EXEC system documentation supplied with the bid documents was supposedly what all their customers used, and it certainly did not help their cause that the manuals had been mastered on a badly out-of-adjustment drum printer. Our informal analysis was that the baselines looked like the path of an earthworm, on LSD, working its way through a brick of soft butter. > A few of IBM's manuals were typeset conventionally, like System/360 > Principles of Operation. Many were reproduced from printout on a TN > print train. most of the manuals started out normal typeset ... there was some transition with cp67 moving documents into (cms) script (cp67/cms morph of ctss runoff) ... with output to 1403 TN print train used as master for printing (usually using "film" ribbon, rather than standard fabric ribbon). Some number of "smaller" documents were done using 2741 as output (instead of 1403, using selectric "film" ribbon).

recent post mentioning film ribbon (and 3800 laser printer) ~lynn/2010p.html#18 Rare Apple I computer sells for $216,000 in London principles of operation was one of the first (outside the cp67 group) to move to cms script; (as mentioned before) because of being a subset of the "architecture manual". moved to cms script ... the full document was the architecture "red book" (named for being distributed in red 3-ring binder). using script command line options, it was possible to print only the "principles of operation" subset (w/o all the internal-only stuff ... like engineering notes and/or discussions of things like alternatives and trade-offs). recent post mentioning "red-book" ~lynn/2010b.html#11 Happy DEC-10 Day GML was also invented at the science center (in 1969) and gml "tag" supported was added to script processing (in addition to "runoff" controls). decade later GML morphed into ISO SGML standard (another decade then saw SGML morph into HTML).

recent post mentioning ctss runoff, script, gml, sgml, html, slac vm/cms having 1st webserver outside cern, etc advent of laser printers (like 3800) eliminated the (1403/impact) computer output characteristic PCW9512 Daisywheel printer PCW9512 Daisywheel printer Care and repair of the PCW9512 & 9512+ daisywheel printer. Update 12th May 2003 The armature, a major spare for repairing the Daisywheel printer is no longer being made and is now hard to come by. As far as I know there is no lasting way of repairing a fractured armature so if that’s your problem you now have a stylish doorstop. There are still a few about at the time of writing at about £6 each – try the suppliers on my weblinks page. The answer is to use a different compatible printer, dot matrix, inkjet or laser – see my report here Description The printer was originally supplied with two covers, front and rear, a tractor unit, ribbon and one printwheel.

The front cover, down in its working position operates a limit switch at the left-hand side. If the switch is not operated the printer will not work. To fit a daisywheel the lever at the top left of the printhead is pulled back, the daisywheel is dropped into its guide cage, making sure that the type face is towards the paper and the lever is pushed forward fully, when the daisywheel clips over its central shaft. When the printer is first used the shaft will spin and the daisywheel will be picked up on a locating pin to ensure correct orientation. Power and data cables terminate in a single 7-pin round plug which plugs into the rear of the monitor. Never plug this in with the machine switched on or you will probably damage the CPU board of the machine!! The printer is quite robust, but some faults occur which can be rectified by the owner. When undertaking repairs always allow plenty of time, take notes or do sketches to remind yourself of how to reassemble; don’t rely on memory alone. Work on a soft cloth to prevent small screws and other parts from flying away. Never use force; if parts won’t separate or fit back together easily find out why before proceeding.

Fractured Armature This is the most common fault and is characterised by the printed characters becoming progressively fainter although the printer seems to be working OK. and the ribbon is good.(see below) To check it remove the printer covers and ribbon. Push the carriage to the left-hand side. If you look into the right-hand side of the carriage you will see an electrical winding, actually an electro-magnet or solenoid, and between this and the rod on which the carriage slides is the armature, sometimes called the hammer. Each time a character is printed the armature is pulled forcibly towards the magnet, striking the type operating lever, which in turn hits the type character against the ribbon and paper. After a long period of time this abuse might cause a fracture to occur in the armature so that it doesn’t push the type operating lever to strike the type character forcibly enough. The fracture is often, but not always, easily seen using a magnifying glass. The only real solution is to replace the armature, not a very daunting job. The armature is located on a shaft at its lower end and secured by a small C-type circlip. This circlip must be pushed out of its groove without losing it.

One way is to fold a piece of soft cloth many times to form a pad which can be located securely under the circlip to catch it. Another tip is to put a little adhesive such as prittstick or even a dab of grease on the circlip so that it will stick to surfaces rather than bounce away. Having removed the circlip the armature can be drawn off its shaft. When the armature has been removed a spring can be seen which presses on the back of the armature and directs it towards the solenoid. When the replacement armature is being fitted this spring must be drawn back to allow the armature to go to its correct position after which the spring can be released to press the armature towards the solenoid.. A simple tool can be made from a piece of wire such as a straightened paperclip. Just bend the end of the wire for about 3mm at right angles and use it to hook the spring and pull it back. The spring position can be checked by pushing the type operating lever towards the daisywheel, when the armature can be seen to move towards the solenoid by pressure from the spring.After this the circlip must be replaced, again taking precautions to prevent it flying away.

Sometimes the spring becomes brittle and can break, but don’t despair; the printer works OK without it. I find it fairly easy to change the armature as detailed above, but if you wish better access can be obtained by removing the top cover and lifting the printer mechanism out as detailed below. What if the replaced armature doesn’t completely cure the problem? Sometimes, even after replacing the fractured armature, the printer persists in printing too lightly or dropping out characters even though the remaining text looks strong. First check the daisywheel disk to ensure that it is in good order, then check the software setting. Bring up the impression strength menu and see whether a stronger impression will cure the problem. If not,there are several ways in which the strike can be improved The strength of the impression is affected by the rebound lever which cushions the return of the striker lever after each character is typed. At rest the striker arm rests against a small rubber buffer on the rebound arm which sets the start position of the striker. Positioning the striker arm a little nearer to the daisywheel often improves the strike and thus the impression, but this can be overdone. There is an optimum position and to overdo it only worsens the impression again.

We are only talking about a millimetre or less and this can be done by sliding a packer of wood or plastic in behind the buffer. A paring from a matchstick will do the job. If it works it should then be glued in place. This should be tried first as it involves no dismantling. An adjustment on the printer’s PC board also affects the strike. To do this remove the top half of the casing as described below, and the printer’s printed circuit board will be seen at the rear. About in the middle of the board you will see a large rotary variable resistor which has a slot for adjustment by screwdriver. By adjusting the resistor, more or less voltage can be applied to the coil driving the armature, thus increasing or decreasing the typing force. Make a short file containing a single line, using those characters which seem most vulnerable. The = is often one such. Tie back the limit switch which is normally operated by the front cover (or the printer won’t run) and type the line. Now adjust the resistor and reprint the line. If it is worse you’re probably turning the resistor the wrong way.

If possible use an insulated screwdriver to do this, but in any case be very careful not to let any metal part cause a short circuit. Turn the resistor a little at a time, checking as you go. When the impression is OK leave it! Don’t be tempted to give it “just a little more”. I have also been told that the solenoid that operates the armature can be adjusted positionally but I have never tried this myself. Ribbons The ribbon being used may also cause problems. The inked nylon type is reliable but doesn’t give the best impression. That is achieved by the carbon faced ribbon often called multistrike. But some of these carbon ribbons break up on contact, causing a very bad impression even on a good machine. When examined, the carbon appears to be almost completely removed from the ribbon, leaving the transparent plastic base, whereas a good ribbon retains a lot of the carbon. If your printer displays these symptoms suspect the ribbon first. These duff ribbons are sold by the most reputable companies so are probably OK for a different type of printer.

When buying a ribbon for your PCW9512 or PcW9512+ ensure that the model number is on the box or ask for confirmation that the ribbon is suitable. Amstrad ribbons are OK Printer appears to work correctly but prints nonsense This is caused by the printwheel not clipping on to its shaft properly, so that the wheel is not indexed but turns at random. When refitting a print wheel make sure that you push the lever quite hard as far as it will go. If you examine the hole at the centre of the wheel you see a spring clip which should engage in a slot in the shaft. If this clip is too tight or the mechanism is slightly worn, the wheel will not go right home. A gap will be seen between wheel and support plate which shouldn’t be there. There are several remedies according to circumstances. Maybe the clip at the centre can be eased off a little or a tiny spot of grease or vaseline applied. If you don’t intend changing the wheel often a thin blade may be introduced to help press the wheel on to its shaft. A more permanent repair can be effected by removing the whole carriage from the printer and adjusting the plate which pushes the wheel on to its shaft.

Remove the top half of the casing. Remove five screws which hold the casing. Look inside the front edge of the casing at the joint and three locking lugs will be seen, one in the centre, the others at the extreme ends. Using a thin screwdriver or something similar carefully release the lugs one at a time until the two halves of the casing can be separated without breaking the lugs off. Look at the way the cables at each side of the mechanism are run in their clips and memorise for replacement purposes later. Lift the printer mechanism up a little by the rail at the front until it clears the locating sockets at the front and draw it out of the two restraining sockets at the rear, releasing the cable at the right hand side from its clip. Release the two clips at the rear of the carriage which hold the retaining plate to the rail and remove the plate. Remove the C circlip at the extreme end of the slide rod. The carriage assembly and slide rod can now be lifted clear. If you find it easier the slide rod can be slid out from the carriage assembly.

By removing the circlip and top plate from the right-hand belt pulley, the belt can be released giving greater movement for the carriage assembly, but don’t release the belt from the carriage assembly; it’s not necessary. Examine the mechanism by loading in the daisywheel a couple of times and you will see that the wheel is pushed on to its shaft by a plate or bar. Bend this plate a little at the centre between both thumbs and forefingers until it engages the wheel and shaft convincingly, but don’t overdo it. Reassemble the printer, making sure that the cables go back into their clips and are not trapped under the printer mechanism and retest. When loading single sheets the paper does not stop but continues feeding with a judder. This is probably not a fault in the printer but is caused by the software. The machine is sending signals to a sheet feeder when one is not fitted. To check this in Locoscript, at the management screen press [PTR] then Options, [f8]. You will probably find that the sheet feeder option is ticked. Cancel it and all will be well.

In CP/M, with the boot disc still in the drive type DAISY SS then press [RETURN] This will set up the printer for (S)ingle (S)heet and the new parameters will come up on screen. Printer carriage moves erratically so that margins are affected or printhead may hit stops This is often caused by dirt or dryness of the bright rod which guides the print head and imposes an extra load on the drive belt which leads to the belt jumping over teeth. Clean the rod with meths and lubricate sparingly along it’s length with a light oil, such as sewing machine oil. This should form part of a regular maintenance routine, along with cleaning. Cleaning Whilst the printer is stripped down, brush or blow out any dust and clean as necessary with a cotton cloth and methylated spirit. The covers and upper case can be washed in warm water and detergent. Make sure that they are dry before refitting. Clean the roller with a cloth or cotton wool soaked in methylated spirit. Rub the roller vigorously whilst turning until very little more ink comes off. These notes are given in good faith and I hope that you will find them of use, but I can accept no responsibility for damage that you may do to your printer in using them.

I have done all these repairs myself several times with different printers and consider that they should not present difficulties. January 2017

Question: Daisywheel, dot-matrix, and laser are all types of what?
Answer: Printers